Alternate action mechanism with plate and dual pin latching means

ABSTRACT

A switch of the type comprising a push button provided with moving contacts and slidably mounted in a fixed casing supporting terminals connected respectively to the phases of a source of power and an appliance, the said contacts being able to come into contact with said terminals to establish the connection between the supply and the appliance when the push button is depressed a first time against the action of resilient return means, so as to move away from the fixed terminals, thus cutting the connection when the push button is depressed a second time and so on, and a locking member being interposed between at least one wall of the push button and an adjoining wall of the casing so as to be able to lock the push button in an open or closed position.

United States Patent [191 Alexander Oct. 16, 1973 ALTERNATE ACTION MECHANISM WITH PLATE AND DUAL PIN LATCHING MEANS [76] Inventor: Percy P. Alexander, Impasse Perrin US. Cl. 200/153 J Int. Cl. H01h 13/56 Field of Search 200/1'53 J, 159 R,

[56] References Cited UNITED STATES PATENTS FOREIGN PATENTS OR APPLICATIONS 1,212,545 3/1960 France 200/153 J 733,974 10/1932 France 200/159 R 1,367,668 6/1964 France 200/153 .1

Primary Examiner-Robert K. Schaefer Assistant Examiner-Robert A. Vanderhye Attorney-Eric H. Waters et al.

[57] ABSTRACT A switch of the type comprising a push button provided with moving contacts and slidably mounted in a fixed casing supporting terminals connected respectively to the phases of a source of power and an appliance, the said contacts being able to come into contact with said terminals to establish the connection between the supply and the appliance when the push button is depressed a first time against the action of resilient return means, so as to move away from the fixed terminals, thus cutting the connection when the push button is depressed a second time and so on, and a locking member being interposed between at least one wall of the push button and an adjoining wall of the casing so as to be able to lock the push button in an open or closed position.

5 Claims, 9 Drawing Figures ALTERNATE ACTION MECHANISM WITH PLATE AND DUAL PIN LATCHING MEANS The present invention relates to a switch of the type comprising a push button provided with moving contacts and slidably mounted in a fixed casing supporting terminals connected respectively to the phases of a source of power and an appliance, the said contacts being able to come into contact with said terminals to establish the connection between the supply and the appliance when the push button is depressed a first time against the action of resilient return means, and to move away from the fixed terminals, thus cutting the connection when the push button is depressed a second time and so on.

Switches of this type are currently used in domestic electrical appliances. They can be found, for example, in bedside lamps, office lights, electric cookers, etc. The closing and opening of these switches is always effected by fully depressing the push button. The principle of the push button switch has other applications, for example in certain ball pens the extension or retraction of the ball takes place by fully depressing a push button.

The object of the present invention is to provide a switch of the aforesaid type which is of simple construction, moderate price, can be quickly fixed and is small in size whilst having an excellent breaking capacity.

Briefly, the switch according to the invention is characterised in that between at least one wall of the push button and one adjoining wall of the casing a locking member is interposed comprising a first pin engaging in a slot perpendicular to the direction of movement of the push button provided on said adjoining wall of the casing, and a second pin able to slide, when the push button is moved relative to the casing, in a guide groove which is closed and cut in said wall of the push button, said guide groove comprising in manner known per se a lower portion and an upper portion, both having a recess directed towards the top of the push button and connected by two different paths, such that each time the push button is fully depressed in the casing then released, the second pin of the locking member is alternately locked, under the action of elastic return means, in one of the said concave portions, on each occasion making use of one of said paths, thus locking the push button in the open or closed position.

According to a particular embodiment of the invention the guide groove is, in manner known per se, substantially heart-shaped and has edges fulfilling the function of cams intended to guide the second pin of the locking member successively from the bottom of the lower concave portion which corresponds to the open position of the push button, towards the first path of the groove, then towards the bottom of the upper concave portion which corresponds to the closed position of the push button, then towards the second path of the gaged, by means of its outer pin, with said slot and, by means of its inner pin with the heart-shaped guide groove or with the elongated groove or with one of the holes.

This embodiment is particularly suitable since it includes three different functions on the same switch. In fact, when the locking member co-operates with the heart-shaped groove by the intermediary of its inner pin, the switch is of the push/push type, the operation of which has been explained above. The switch may be closed or opened as desired and kept in the chosen position for the desired period. If at present, the inner pin of the locking member is engaged in the vertical groove, the push button is normally urged by elastic return means towards its outwards open position; contact is established momentarily as long as one presses on the button, until the inner pin comes into abutment with the upper end of the vertical groove. This arrangement is advantageous when it is desired to check, for example on an appliance, if the operating temperature has reached the desired value, or if in an electric oven with a thermostat,.the cooking is completed. Finally, when the inner pin is engaged in one of the holes, the push button remains either in a closed position or an open position. The result is that due to the provision on the wall of the push button of a heart-shaped groove, an elongated groove and two holes, it is possible to provide switches, control members and static components respectively such as signal lamps, all having the same appearance.

According to a particular embodiment of the invention, the push button comprises a button extending by means of two vertical and parallel walls, on the outer face of which are cut the guide grooves and at least two vertical slots serving for receiving the end of two horizontal metallic contacts connecting the two vertical walls. In this embodiment it is naturally possible to provide two locking members, the inner pins of which cooperate with the corresponding guide groove on the walls of the push button and the outer pins of which are engaged in corresponding slots in the casing.

A small column projecting up under the button passes through each of the moving contacts with clearance, in its central portion, around which column there is placed a compensated spring supported on the button and on the contact, so as to normally urge the latter towards a position in which its ends are located in abutment against the lower end of the vertical slots. The compensating springs ensure that the moving contacts are fully applied against the terminals of the casing, even when the push button is released after having been closed.

The elastic return means are constituted by at least one spring supported on the lower wall of the casing and passing through an axial guide housing, provided between two strips extending the corresponding wall of the push button.

According to an advantageous embodiment of the invention, the said strips are guided, during the closing movement of the push button, by the walls of a lower portion of the casing of corresponding section.

The invention will now be further described by way of example only with reference to the accompanying drawings in which:

FIG. 1 is an exploded perspective view of one embodiment of push button switch according to the invention, the casing and the push button being assumed to be made of transparent material;

FIG. 2 is a sectional view along the line II-Il of FIG. 1, the push button being in open position;

FIG. 3 is a partial sectional view along the line IIIIII of FIG. 1;

FIG. 4 is an elevation of the locking member;

FIG. 5 is an elevation of a moving contact;

FIGS. 6 and 7 show the switch in the open position from two different angles; and

FIGS. 8 and 9 show the switch in the closed position.

The switch illustrated in FIGS. 1 and 2 comprises essentially a casing 1 and a push button 2 slidably mounted in the casing. The push button and the casing are constituted of an insulating and preferably transparent material, for example of plexi-glass. The casing is intended to be secured to a support member of an appliance, for example by clips not shown.

Referring to FIGS. 1 and 2, the casing 1 comprises an upper part 3 of substantially cubic shape, open at its upper side and a lower part 4 of reduced cross-section. The part 3 has a rim 5 which may be covered by a cover 6 of chrome metal (see FIG. 2). Two vertical opposed walls of the part-3 of the casing each have a horizontal slot 7 the function of which will be described hereafter. Stationary terminals 8, 9, 10 and 11 of copper or brass pass through the bottom of the part 3, on either side of the lower part 4. The terminals 8, 9 are connected for example, by their part which is outside the casing, to the phases of the power supply, whereas the terminals 10, 11 are connected to the appliance on which the switch is mounted. The terminals have a horizontal bent part to which a metal contact 12 is connected constituted by a copper rivet, the head of which is covered by a film of silver, ensuring a non-resistant contact with the moving contacts of the push button. Stationary terminals 14, 15 pass through the bottom of the lower part 4, which terminals are connected on the one hand to the appliance terminals 10, 11 by leads not shown, and on the other hand to an indicator lamp 16 in series with its resistance 17.

The push button 2 comprises a button 23 of square section to which the pressure of the finger is applied. The button is terminated by a base 24 passing with some clearance through the aperture in the upper part 3 of the casing. As shown in FIG.2, the button is covered by a transparent cover 25 preferably constituted of coloured plastics material. The cover is fixed to the button by the penetration of small projections provided on the walls of the button in corresponding holes of the cover. When the cover is in place, it covers exactly the upper rim of the base 24.

Two opposed faces of the button extend uner the base in the form of two parallel walls each provided with two vertical slots 27 located in the vicinity of the side edges of the wall. Each of the slots of one wall and the opposed slots of the second wall receive the tapered ends 28 of a moving contact 29 of copper or brass, the shape of which is clearly illustrated in FIGS. The contact 29 comprises two studs 30 constituted by copper rivets whose heads are covered with a film of silver. The arrangement is such that when the push button 2 is depressed in the casing 1, the studs 30 of the moving contacts 29 are applied exactly against the studs of the stationary contact 8 to 11. In their central portion, the contacts comprise a hole 31 through which there slides a small column 32 of insulating material, projecting under the button 23. The two moving contacts 29 are normally urged towards their lower position in which their ends 28 press against the bottom of the corresponding slots 27, due to compensation springs 33 fitted around the small columns and pressing on the moving contacts and on the base 34 of the small columns. Each of the walls 26 is terminated by two parallel and relatively thick strips 35, providing between them an axial housing 36 intended to receive a return spring 37. The width of the strips is such that the latter may be guided by the vertical walls of the lower part 4 during the movement of the push button in the casing.

On the outer side of each of the walls 26 and between the vertical slots 27 there are provided grooves 38 intended to guide a locking member 39 illustrated in FIG.4. The locking members 39 serve to provide a connection between the push button and the casing and to prevent the push button from being pushed out of the casing under the action of the return spring 37. The locking member comprises a thin disc 40 provided on its faces with two cylindrical pins 41 and 42. As shown in FIGS. 6 and 8 the locking member is engaged in the space separating the wall 26 of the push button and the adjoining wall of the casing, such that the pin 42 is located in the slot 7 and the pin 41 engaged in a groove 38. The diameter of the disc 40 is greater than the width of the slot in order that the locking member can-v not escape from the slot. Naturally, a second locking member may also be mounted between the second wall 26 of the push button and the corresponding wall of the casing.

FIG. 3 clearly shows the shape of the guide grooves. The first groove 43 is substantially heart shaped. It is composed of a closed shape successively comprising a concave part AB, a cam surface EC inclined towards the right, a vertical surface CD, a cam surface DE inclined towards the left, a notch EF, a cam surface FG inclined towards the left, a notch Gl-I, a cam surface I-ll, a vertical surface II and finally a cam surface JA inclined towards the right and connected to the concave portion AB. The inner edge of the groove 43 comprises a cam surface KL inclined in an upwards direction, a vertical surface LM, a cam surface MN inclined towards the left, a concave portion NO, a cam surface OP inclined towards the left and a cam surface PK incldined towards the right. FIG. 3 shows the path travelled by the geometric axis of the pin 41-during a cycle comprising an opening and closing.

On either side of the heartshaped groove 43 there are located a vertical groove 44 and two holes 45 and 46 whose function have been previously explained.

The operation of the switch is illustrated by FIGS. 6 to 9; FIGS. 6 and 7 show the switch in the open position. The push button 2 is thus locked in its upper posi- -tion for which the pins 41 of the two locking members 39 are in abutment at the bottom of a concave portion AB. If the push button is depressed slightly then released, it returns resiliently to its initial position under the action of the return springs'37. In this open position the moving contacts 29 are separated from the terminals 8 to 11 and are pressed by the compensating springs against the base of the vertical slots 27.

When the push button is depressed progressively in the casing against the force of the return springs 37, the moving contacts 29 are applied against the fixed terminals'8 to 11 thus establishing connection between the source of power and the appliance. The indicator lamp 16 is immediately illuminated and can be seen through the coloured cover 25. Simultaneously on each wall 26, the pin 41 of the locking member moves vertically inside the groove 43 (see FIG.3) then parallel to the cam surface KL. During this latter movement, the locking member is urged towards the right, its outer pin 42 moving in the same direction in the slot 7. 1f the push button is depressed further, due to the fact that the moving contacts are immobilised by the stationary contacts, the small columns 32 slide in the corresponding holes 31 of the contacts, the compensating springs 33 are compressed and the tapered ends 28 of the moving contacts are raised in the vertical slots 27. The pin 41 is then moved vertically in the passage formed between the surfaces LM and CD. If the push-button is released at this moment, it returns to its initial open position under the action of the return spring 37. In this movement, pin 41 passes down the vertical passage then is deflected by the cam surface CB towards the bottom of the concave portion.

Since the pin 41 is located at the upper end of the vertical pasage, if the push button is depressed still further, it is deflected by the cam surface DE towards the bottom of the notch EF. The push button is at the end of its lower stroke and the return spring 37 as well as the compensating springs are thus compressed to a maximum. The push button is then released. Under the action of the return springs, it moves partially upwards, since the pin 41, travelling downwards in the notch EF, is intercepted by the cam surface MN which guides it to the bottom of the concave portion NO. Inthis position the locking member prevents the push button from moving upwards completely into its open position. The switch is thus closed. This position is illustrated by FIGS. 8 and 9.

In order to open the switch, it is sufficient to depress the push button fully and release it. In fact, by depressing the push button the pin 41 rises vertically then is deflected to the left by the cam surface FG towards the notch GH. When the push button is released, it is returned upwards by the springs 33 and 37. The pin 41 thus descends along the notch GE, is intercepted by the cam surface OP, follows the surface I] and is finally returned to the bottom of the concave portion AB by the cam surface JA. When the pin is located approximately at the centre of the cam surface JA, the push button has risen sufficiently for the moving contacts 29, raised at their ends by the slots 27, to move away from the fixed terminals 8 to 1 l. Simultaneously, the indicator light 16 goes out. The mounting of the switch takes place in the following manner.

After having placed the compensating springs 33 around the small columns 32, the ends of the latter are introduced into the hole 31 of the corresponding moving contact 29, then by making use of the elasticity of the walls 26, the ends 28 of the contacts 29 are engaged in the vertical slots 27. In turn, the casing is provided with fixed terminals 8 to 11 and 14, with its indicator lamp l6 and return spring 37. The inner pin 41 of the locking member 39 is then engaged in the groove 43 of the wall 26 by slightly separating the walls of the casing, the push button and the locking member are slid into the upper aperture of the casing until the outer pin 42 projects through the slot 7. During the introduction of the push button into casing the return spring 37 is engaged in the corresponding housing-35. The push button is thus locked in the casing. in order to use the groove 44 or the holes 45,46 of the push button, the mounting is effected as previously, except that the inner pin 41 is engaged in the desired groove before the push button is introduced into the casing.

I claim:

1. Switch of the type comprising a push button provided with moving contacts and slidably mounted in a stationary casing supporting terminals adapted to be connected respectively to the phases of a source of a power and an appliance, said contacts being able to rest on said terminals to establish the connection between the supply and the appliance when the push button is depressed for a first time against the action of resilient return means and to move away from the stationary contacts thus cutting this connection when the push button is depressed for a second time and so on, characterized in that between at least one wall of the push button and one adjoining wall of the casing a locking member is interposed comprising a first guide pin engaging in a slot perpendicular to the direction of movement of the push-button provided on said adjoining wall of the casing, a second guide pin able to slide in a guide groove which is closed and cut into said wall of the push button when the push button moves relative to the casing, and a thin plate being formed intermediate said first and second guide pins, said plate beind dimensioned so as to be greater than the width of the slot in said casing, said guide groove comprising a lower part and an upper part both having a concave part. directed towards the top of the push button and connected by two different paths, such that each time the push button is fully depressed in the casing and then released, the second guide pin of the locking element is alternately locked, under the action of the resilient return means, in one of the said concave portions, utilizing each time one of said paths, thus locking the push button in the open or closed position.

2. Switch according to claim 1, characterized in that there are also cut in the wall of the push button which comprises the heart-shaped guide groove an elongated groove, parallel to the direction of movement of the push button and two holes located vertically to positions corresponding respectively to the depressed and projecting positions of the push button the slot of the casing being sufficiently elongated inorder that the pin, with said slot, and, by its inner pin, either with the heart-shaped groove or with the elongated groove or with one of the holes.

3. Switch according to claim 1, characterized in that the resilient return means are constituted by at least one spring supported on the lower wall of the casing and passing through an axial guide housing provided between two strips extending the corresponding wall of the push button.

4. Switch of the type comprising a push button provided with moving contacts and slidably mounted in a stationary casing supporting terminals adatped to be connected respectively to the phases of a source of a power and an appliance, said contacts being able to rest on said terminals to establish the connection between the supply and the appliance when the push button is depressed for a first time against the action of resilient return means an to move away from the stationary contacts thus cutting this connection when the push button is depressed for a second time and so on, characterized in that between at least one wall of the push button and one adjoining wall of the casing a locking member is interposed comprising a first guide pin engaging in a slot perpendicular to the direction of movement of the push button provided on said adjoining wall of the casing, and a second guide pin able to slide in a guide groove which is closed and cut into said wall of the push button when the push button moves relative to the casing, said push button extending by means of two vertical and parallel walls, in the outer face of which is cut the guide groove and at least two vertical slots receiving respectively the ends of two horizontal metal contacts connecting the two vertical walls, said guide groove comprising a lower part and an upper part both having a concave part directed towards the top of the push button and connected by two different paths, such that each time the push button is fully depressed in the casing then released, the second guide pin of the locking element is alternately locked, under the action of the resilient return means, in one of the said concave portions, utilizing each time one of said paths, thus locking the push button in the open or closed position.

5. Switch according to claim 4, characterized in that a small column projecting below the button passes with some clearance through each of the mobile contacts in its center part, and around which column there is placed a compensating spring supported on the button and on the contacts, so as to normally urge the latter towards a position in which its ends are located in abutment at the lower end of the vertical slots. 

1. Switch of the type comprising a push button provided with moving contacts and slidably mounted in a stationary casing supporting terminals adapted to be connected respectively to the phases of a source of a power and an appliance, said contacts being able to rest on said terminals to establish the connection between the supply and the appliance when the push button is depressed for a first time against the action of resilient return means and to move away from the stationary contacts thus cutting this connection when the push button is depressed for a second time and so on, characterized in that between at least one wall of the push button and one adjoining wall of the casing a locking member is interposed comprising a first guide pin engaging in a slot perpendicular to the direction of movement of the pushbutton provided on said adjoining wall of the casing, a second guide pin able to slide in a guide groove which is closed and cut into said wall of the push button when the push button mOves relative to the casing, and a thin plate being formed intermediate said first and second guide pins, said plate being dimensioned so as to be greater than the width of the slot in said casing, said guide groove comprising a lower part and an upper part both having a concave part directed towards the top of the push button and connected by two different paths, such that each time the push button is fully depressed in the casing and then released, the second guide pin of the locking element is alternately locked, under the action of the resilient return means, in one of the said concave portions, utilizing each time one of said paths, thus locking the push button in the open or closed position.
 2. Switch according to claim 1, characterized in that there are also cut in the wall of the push button which comprises the heart-shaped guide groove an elongated groove, parallel to the direction of movement of the push button and two holes located vertically to positions corresponding respectively to the depressed and projecting positions of the push button the slot of the casing being sufficiently elongated in order that the locking member may be engaged, by means of its outer pin, with said slot, and, by its inner pin, either with the heart-shaped groove or with the elongated groove or with one of the holes.
 3. Switch according to claim 1, characterized in that the resilient return means are constituted by at least one spring supported on the lower wall of the casing and passing through an axial guide housing provided between two strips extending the corresponding wall of the push button.
 4. Switch of the type comprising a push button provided with moving contacts and slidably mounted in a stationary casing supporting terminals adapted to be connected respectively to the phases of a source of a power and an appliance, said contacts being able to rest on said terminals to establish the connection between the supply and the appliance when the push button is depressed for a first time against the action of resilient return means and to move away from the stationary contacts thus cutting this connection when the push button is depressed for a second time and so on, characterized in that between at least one wall of the push button and one adjoining wall of the casing a locking member is interposed comprising a first guide pin engaging in a slot perpendicular to the direction of movement of the push button provided on said adjoining wall of the casing, and a second guide pin able to slide in a guide groove which is closed and cut into said wall of the push button when the push button moves relative to the casing, said push button extending by means of two vertical and parallel walls, in the outer face of which is cut the guide groove and at least two vertical slots receiving respectively the ends of two horizontal metal contacts connecting the two vertical walls, said guide groove comprising a lower part and an upper part both having a concave part directed towards the top of the push button and connected by two different paths, such that each time the push button is fully depressed in the casing then released, the second guide pin of the locking element is alternately locked, under the action of the resilient return means, in one of the said concave portions, utilizing each time one of said paths, thus locking the push button in the open or closed position.
 5. Switch according to claim 4, characterized in that a small column projecting below the button passes with some clearance through each of the mobile contacts in its center part, and around which column there is placed a compensating spring supported on the button and on the contacts, so as to normally urge the latter towards a position in which its ends are located in abutment at the lower end of the vertical slots. 